#include <iostream>

using namespace std;

class Solution {
public:
    int trailingZeroes(int n) {
        int count = 0;
        while (n >= 5) {
            int cur_count = n / 5;
            count += cur_count;
            n = cur_count;
        }
        return count;
    }
};

int main() {
    Solution solution;
    int output = solution.trailingZeroes(4);
    cout << output << endl;
    return 0;
}

